From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0539C4346E for ; Tue, 29 Sep 2020 07:13:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8DE6E2083B for ; Tue, 29 Sep 2020 07:13:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="fK104d7b" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727474AbgI2HNx (ORCPT ); Tue, 29 Sep 2020 03:13:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725710AbgI2HNx (ORCPT ); Tue, 29 Sep 2020 03:13:53 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A6E4C061755 for ; Tue, 29 Sep 2020 00:13:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ELXndXXTSP15bhYlf8giv2I6wKSj/3tGXdDNG1yeq8I=; b=fK104d7bBl2CIgFMxM8svO3BA1 hY2IzK2/lLOU2NZ+jZUqL4qyCpZTmpGi8YXEz6Pfan/Xf0HwWHAQzDrxBLfie6SBHcgOem3oum6an S2POnkB9xQCAt/IyGv35e38B1boGtIrevNPp8BkSplBuUFqNM2cy7FDtx/yiNrH31Q/s+EW7p37P6 vzjNO/kln+LGrfQ3CCRIEw8Esoo1a6En/LfUOoqTkGwPsNYd9bjBG0Phh6MPVDkPaSdPpexDJ/r8c ulvTjcoGhOoVJP8Aw2nYFy+86QjIMBIKNdLeYdOvEgzNMNwMhpxs6jctznJBzW4wzv2CpVBiHkrcF 7TQ1bjBw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kN9pR-0000Hx-Hx; Tue, 29 Sep 2020 07:13:37 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 1E1B1300F7A; Tue, 29 Sep 2020 09:13:34 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 0798D211CC1CC; Tue, 29 Sep 2020 09:13:34 +0200 (CEST) Date: Tue, 29 Sep 2020 09:13:33 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: quanyang.wang@windriver.com, linux-kernel@vger.kernel.org, Thomas Gleixner , Leo Yan , Will Deacon , a.darwish@linutronix.de, Daniel Lezcano , Paul Cercueil , Randy Dunlap , ben.dooks@codethink.co.uk Subject: Re: [PATCH] time/sched_clock: mark sched_clock_read_begin as notrace Message-ID: <20200929071333.GK2628@hirez.programming.kicks-ass.net> References: <20200928104952.26892-1-quanyang.wang@windriver.com> <20200928105859.GF2628@hirez.programming.kicks-ass.net> <20200928173331.3ea3cfb7@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200928173331.3ea3cfb7@oasis.local.home> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 28, 2020 at 05:33:31PM -0400, Steven Rostedt wrote: > On Mon, 28 Sep 2020 12:58:59 +0200 > Peter Zijlstra wrote: > > > > -struct clock_read_data *sched_clock_read_begin(unsigned int *seq) > > > +notrace struct clock_read_data *sched_clock_read_begin(unsigned int *seq) > > > { > > > *seq = raw_read_seqcount_latch(&cd.seq); > > > return cd.read_data + (*seq & 1); > > > > At the very least sched_clock_read_retry() should also be marked such. > > > > But Steve, how come x86 works? Our sched_clock() doesn't have notrace on > > at all. > > It's because of that magic in the Makefile that you love so much ;-) > > CFLAGS_REMOVE_tsc.o = -pg ARGH!!, I really should write a script to fix up that mess :/